Antiperspirant compositions are known to experts in many forms. Astringent substances, for example aluminium and/or zirconium salts, are normally used as the antiperspirant agents. The compositions are marketed as sprays, roll-on preparations, sticks or creams. Formulations such as these are described in Cosmetics: Science and Technology, “Antiperspirants and Deodorants” (Ed: M. S. Balsam and E. G. Sagarin, 1972), Vol. 2, pp. 373-416 by S. Plechner and in Cosmetics Science and Technology Series: “Antiperspirants and Deodorants” (Ed: Karl Laden), 2nd Edition, pp. 233-258 and pp. 327-356.
Whereas the cosmetics market has been dominated by stick preparations in recent years, cream-like antiperspirant preparations are enjoying increasing popularity. Many antiperspirant creams, such as those described in EP 0 310 252, WO 91/04009, WO 97/16161, WO 97/17942, WO 98/51185, WO 98/27947, U.S. Pat. No. 4,863,721, U.S. Pat. No. 4,937,069 and U.S. Pat. No. 5,292,530, are formulated without water. Preparations such as these leave a pleasantly dry feeling behind on the user's skin after application. However, effective release of the particulate antiperspirant agents from such preparations is limited by comparison with water-containing formulations (cf.: Chemistry and Technology of the Cosmetics and Toiletries Industry, Ed.: D. F. Williams and W. H. Schmitt, London: Blackie, 1996, 2nd Edition, page 326), besides which the preparations often fail to leave the skin feeling fresh. In addition, water-free antiperspirant preparations based on volatile silicone oils have the disadvantage that the dispersed antiperspirant agents easily lead to visible product residues on the skin and clothing. If pressure is applied during application, “oiling out” (syneresis) often occurs and reduces the cosmetic acceptance of the preparations among users.
By contrast, water-containing emulsion-like antiperspirant creams such as those described, for example, in U.S. Pat. No. 4,268,499, WO 97/48373 and WO 98/27946 have the disadvantage that they leave an unpleasant and long-lasting feeling of wetness behind after application to the skin and are often found by users to be sticky and greasy.
The problem addressed by the present invention was to provide a water-free antiperspirant composition with improved antiperspirant performance, particularly high dermatological compatibility and optimized release of the antiperspirant agent which would be quickly and completely absorbed by the skin. Another problem addressed by the invention was to provide preferably paste-form antiperspirant compositions (creams) which would have high stability in storage without syneresis of the oil components at room temperature and high temperature stability, would not leave any oily film behind after application to the skin, would create a pleasantly velvety, dry and light impression and would be easy to wash off.